Datasheet SP7652 Datasheet (Sipex)

Page 1
Power
Blox
M
Blox
®
Preliminary
T
Wide Input Voltage Range 6A, 600kHz, Buck Regulator
SP7652
1
2
3
4
5
6
7
8
9
10
11
12
13
SP7652
DFN PACKAGE 7mm x 4mm
TOP VIEW
Heatsink Pad 1 Connect to Lx
Heatsink pad 2 Connect to GND
Heatsink pad 3 Connect to V
IN
26
LX
LX
25
LX
24
23
LX
V
22
CC
GND
21
GND
20
19
GND
18
BST
17
NC
LX
16
LX
15
14
LX
FEATURES
2.5V to 28V Step Down Achieved Using Dual Input
Output Voltage down to 0.8V
6A Output Capability (Up to 8A with Air Flow)
Built in Low R
Highly Integrated Design, Minimal Components
600 kHz Fixed Frequency Operation
UVLO Detects Both V
Over Temperature Protection
Short Circuit Protection with Auto-Restart
Wide BW Amp Allows Type II or III Compensation
Programmable Soft Start
Fast Transient Response
High Efficiency: Greater than 92% Possible
Asynchronous Start-Up into a Pre-Charged Output
Power FETs (15 m typ)
and V
CC
IN
P
GND
P
GND
P
GND
GND
V
COMP
UVIN
GND
V
V
V
V
FB
SS
IN
IN
IN
IN
Small 7mm x 4mm DFN Package
Now Available in Lead Free Packaging
DESCRIPTION
The SP7652 is a synchronous step-down switching regulator optimized for high efficiency. The part is designed to be especially attractive for dual supply, 12V step down with 5V used to power the controller. This lower VCC voltage minimizes power dissipation in the part. The SP7652 is designed to provide a fully integrated buck regulator solution using a fixed 600kHz frequency, PWM voltage mode architecture. Protection features include UVLO, thermal shutdown
and output short circuit protection. The SP7652 is available in the space saving DFN package.
TYPICAL APPLICATION CIRCUIT
5.1K100pF
21.5k,1%
RSET (note 2)
ENABLE
VIN
CF1
100pF
1nF
22pF
12K
1
2
3
4
5
6
7
8
9
CSS 22nF
10
11
12
13
2.5V - 20V
C1 22uF
GND
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
U1
SP7652
PGND
PGND
PGND
GND
VFB
COMP
UVIN
GND
SS
VIN
VIN
VIN
VIN
Notes:
1. U1 Bottom-Side Layout should has three contacts isolated from one another VIN and SWNODE and GND
2. RSET = 54.48 / (Vout - 0.8V) (kOhm)
26
LX
25
LX
24
LX
23
LX
22
VCC
21
GND
20
GND
19
GND
18
BST
17
NC
16
LX
15
LX
14
LX
1
68.1k,1%
1.5uH, Irate=8A
CVCC 1uF
5.1
1uF
5V VCC
SD101AWS
VOUT
3.3V 0-8A
Ceramic X5R 6.3V
47uF
Page 2
These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability.
.................................................................................................. 7V
V
CC
...........................................................................................................................................
V
IN
............................................................................................................................................
I
LX
BST ............................................................................................... 35V
BST-SWN ......................................................................... -0.3V to 7V
SWN ................................................................................... -1V to 30V
30V 10A
GH ......................................................................... -0.3V to BST+0.3V
GH-SWN ......................................................................................... 7V
All other pins .......................................................... -0.3V to V
Storage Temperature .................................................. -65°C to 150°C
Power Dissipation .................................................... Internally Limited
ESD Rating .......................................................................... 2kV HBM
Thermal Resistance ϑ
....................................................................................
JC
ELECTRICAL SPECIFICATIONS
ABSOLUTE MAXIMUM RATINGS
Unless otherwise specified: -40°C < T GND = 0V, UVIN = 3.0V, CV The denotes the specifications which apply over the full temperature range, unless otherwise specified.
= 1µF, C
CC
RETEMARAP.NIM.PYT.XAMSTINUSNOITIDNOC
TNERRUCTNECSEIUQ
< 85°C, -40°C<Tj<125°C, 4.5V < V
AMB
= 0.1µF, CSS = 50nF, Typical measured at V
COMP
< 5.5V, 3V<Vin<28V, BST=LX + 5V, LX =
CC
CC
= 5V.
+0.3V
CC
5°C/W
V
CC
V
CC
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)gnihctiws(tnerruCylppuS1151Am
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)gnihctiws(tnerruCylppuSTSB821Am
V9.0=
BF
OLVU:NOITCETORP
V
CC
V
CC
dlohserhTtratSOLVU00.452.45.4V
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BF
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Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
2
Page 3
Unless otherwise specified: -40°C < T GND = 0V, UVIN = 3.0V, CV The denotes the specifications which apply over the full temperature range, unless otherwise specified.
= 1µF, C
CC
RETEMARAP.NIM.PYT.XAMSTINUSNOITIDNOC
edutilpmApmaR29.01.182.1V
tesffOPMAR1.1V
< 85°C, -40°C<Tj<125°C, 4.5V < V
AMB
= 0.1µF, CSS = 50nF, Typical measured at V
COMP
CC
tneiciffeoC.pmeTtesffOPMAR2-Cº/Vm
< 5.5V, 3V<Vin<28V, BST=LX + 5V, LX =
CC
= 5V.
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T
A
ELECTRICAL SPECIFICATIONS
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Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
3
Page 4
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General Overview
The SP7652 is a fixed frequency, voltage mode, synchronous PWM regulator optimized for high efficiency. The part has been designed to be especially attractive for split plane applications utilizing 5V to power the controller and 3V to 28V for step down conversion.
The SP7652 contains two unique control fea­tures that are very powerful in distributed appli­cations. First, asynchronous driver control is enabled during start up, to prohibit the low side NFET from pulling down the output until the high side NFET has attempted to turn on. Sec­ond, a 100% duty cycle timeout ensures that the
THEORY OF OPERATION
The heart of the SP7652 is a wide bandwidth transconductance amplifier designed to accom­modate Type II and Type III compensation schemes. A precision 0.8V reference, present on
low side NFET is periodically enhanced during extended periods at 100% duty cycle. This guar­antees the synchronized refreshing of the BST capacitor during very large duty ratios.
the positive terminal of the error amplifier per­mits the programming of the output voltage down to 0.8V via the VFB pin. The output of the error amplifier, COMP, which is compared to a
1.1V peak-to-peak ramp is responsible for trail­ing edge PWM control. This voltage ramp, and PWM control logic are governed by the internal oscillator that accurately sets the PWM fre-
The SP7652 also contains a number of valuable protection features. Programmable UVLO al­lows the user to set the exact V
value at which
IN
the conversion voltage can safely begin down conversion, and an internal VCC UVLO ensures that the controller itself has enough voltage to properly operate. Other protection features in-
quency to 600kHz.
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
4
Page 5
THEORY OF OPERATION
clude thermal shutdown and short-circuit detec­tion. In the event that either a thermal, short­circuit, or UVLO fault is detected, the SP7652 is forced into an idle state where the output drivers are held off for a finite period before a re-start is attempted.
Soft Start
“Soft Start” is achieved when a power converter ramps up the output voltage while controlling the magnitude of the input supply source cur­rent. In a modern step down converter, ramping up the positive terminal of the error amplifier controls soft start. As a result, excess source current can be defined as the current required to charge the output capacitor.
I
VIN
= C
OUT
* (DV
OUT
/ DT
SOFT-START
)
The SP7652 provides the user with the option to program the soft start rate by tying a capacitor from the SS pin to GND. The selection of this capacitor is based on the 10uA pull up current present at the SS pin and the 0.8V reference voltage. Therefore, the excess source can be redefined as:
I
= C
VIN
Under Voltage Lock Out (UVLO)
OUT
* (DV
*10µA / (CSS * 0.8V)
OUT
The SP7652 contains two separate UVLO com­parators to monitor the internal bias (VCC) and conversion (VIN) voltages independently. The VCC UVLO threshold is internally set to 4.25V, whereas the VIN UVLO threshold is program­mable through the UVIN pin. When the UVIN pin is greater than 2.5V, the SP7652 is permitted to start up pending the removal of all other faults. Both the VCC and V
UVLO compara-
IN
tors have been designed with hysteresis to pre­vent noise from resetting a fault.
Thermal and Short-Circuit Protection
Because the SP7652 is designed to drive large output current, there is a chance that the power converter will become too hot. Therefore, an internal thermal shutdown (145°C) has been included to prevent the IC from malfunctioning at extreme temperatures.
A short-circuit detection comparator has also been included in the SP7652 to protect against an accidental short at the output of the power converter. This comparator constantly monitors the positive and negative terminals of the error amplifier, and if the VFB pin falls more than 250mV (typical) below the positive reference, a short-circuit fault is set. Because the SS pin overrides the internal 0.8V reference during soft start, the SP7652 is capable of detecting short­circuit faults throughout the duration of soft start as well as in regular operation.
Handling of Faults:
Upon the detection of power (UVLO), thermal, or short-circuit faults, the SP7652 is forced into an idle state where the SS and COMP pins are pulled low and the NFETS are held off. In the event of UVLO fault, the SP7652 remains in this idle state until the UVLO fault is removed. Upon the detection of a thermal or short-circuit fault, an internal 200ms timer is activated. In the event of a short-circuit fault, a re-start is at­tempted immediately after the 200ms timeout expires. Whereas, when a thermal fault is de­tected the 200ms delay continuously recycles and a re-start cannot be attempted until the thermal fault is removed and the timer expires.
Error Amplifier and Voltage Loop
Since the heart of the SP7652 voltage error loop is a high performance, wide bandwidth transconductance amplifier great care should be taken to select the optimal compensation net­work. Because of the amplifier’s current lim­ited (+/-150µA) transconductance, there are many ways to compensate the voltage loop or to
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
5
Page 6
control the COMP pin externally. If a simple, single pole, single zero response is desired, then compensation can be as simple as an RC to ground. If a more complex compensation is required, then the amplifier has enough band­width (45° at 4 MHz) and enough gain (60dB) to run Type III compensation schemes with ad­equate gain and phase margins at cross over frequencies greater than 50kHz.
The common mode output of the error amplifier is 0.9V to 2.2V. Therefore, the PWM voltage ramp has been set between 1.1V and 2.2V to ensure proper 0% to 100% duty cycle capability. The voltage loop also includes two other very important features. One is an asynchronous start up mode. Basically, the synchronous rectifier can not turn on unless the high side NFET has attempted to turn on or the SS pin has exceeded
1.7V. This feature prevents the controller from “dragging down” the output voltage during startup or in fault modes. The second feature is a 100% duty cycle timeout that ensures synchro­nized refreshing of the BST capacitor at very high duty ratios. In the event that the high side NFET is on for 20 continuous clock cycles, a reset is given to the PWM flip flop half way through the 21st cycle. This forces GL to rise for the cycle, in turn refreshing the BST capacitor.
Power MOSFETs
The SP7652 contains a pair of integrated low resistance N MOSFETs designed to drive up to 6A of output current. Maximum output current could be limited by thermal limitations of a particular application. The SP7652 incorpo­rates a built-in over-temperature protection to prevent internal overheating.
THEORY OF OPERATION
V
BST
GH Voltage
V
SWN
V(V
CC)
GL Voltage
0V
V(VIN)
SWN Voltage
-0V
-V(Diode) V
V(VIN)+V(VCC)
BST Voltage
V(VCC)
TIME
Setting Output Voltages
The SP7652 can be set to different output voltages. The relationship in the following formula is based on a voltage divider from the output to the feedback pin VFB, which is set to an internal reference voltage of 0.80V. Standard 1% metal film resistors of surface mount size 0603 are recommended.
Vout = 0.80V ( R1 / R2 + 1 ) => R2 = R1 / [ ( Vout / 0.80V ) – 1 ]
Where R1 = 68.1K and for Vout = 0.80V setting, simply remove R2 from the board. Furthermore, one could select the value of R1 and R2 combination to meet the exact output voltage setting by restricting R1 resistance range such that 50K < R1 < 100K for overall system loop stability.
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
6
Page 7
APPLICATIONS INFORMATION
Inductor Selection
There are many factors to consider in selecting the inductor including core material, inductance vs. frequency, current handling capability, effi­ciency, size and EMI. In a typical SP7652 cir­cuit, the inductor is chosen primarily by operat­ing frequency, saturation current and DC resis­tance. Increasing the inductor value will de­crease output voltage ripple, but degrade tran­sient response. Low inductor values provide the smallest size, but cause large ripple currents, poor efficiency and more output capacitance to smooth out the larger ripple current. The induc­tor must be able to handle the peak current at the switching frequency without saturating, and the copper resistance in the winding should be kept as low as possible to minimize resistive power loss. A good compromise between size, loss and cost is to set the inductor ripple current to be within 20% to 40% of the maximum output current.
The switching frequency and the inductor oper­ating point determine the inductor value as fol­lows:
L−=
(max)
OUTINOUT
IKFV
(max)(max)
OUTrSIN
)(
VVV
where: Fs = switching frequency Kr = ratio of the ac inductor ripple current to the
maximum output current
The peak to peak inductor ripple current is:
)(
VVV
=
I
PP
(max)
(max)
OUTINOUT
LFV
SIN
Once the required inductor value is selected, the proper selection of core material is based on peak inductor current and efficiency require­ments. The core must be large enough not to
saturate at the peak inductor current
I
II +=
(max)
OUTPEAK
PP
2
and provide low core loss at the high switching frequency. Low cost powdered iron cores are inappropriate for 900kHz operation. Gapped ferrite inductors are widely available for consid­eration. Select devices that have operating data shown up to 1MHz. Ferrite materials, on the other hand, are more expensive and have an abrupt saturation characteristic with the induc­tance dropping sharply when the peak design current is exceeded. Nevertheless, they are pre­ferred at high switching frequencies because they present very low core loss and the design only needs to prevent saturation. In general, ferrite or molypermalloy materials are better choice for all but the most cost sensitive appli­cations.
Optimizing Efficiency
The power dissipated in the inductor is equal to the sum of the core and copper losses. To mini­mize copper losses, the winding resistance needs to be minimized, but this usually comes at the expense of a larger inductor. Core losses have a more significant contribution at low output cur­rent where the copper losses are at a minimum, and can typically be neglected at higher output currents where the copper losses dominate. Core loss information is usually available from the magnetic vendor. Proper inductor selection can affect the resulting power supply efficiency by more than 15-20%!
The copper loss in the inductor can be calculated using the following equation:
2
RIP
)()(
WINDINGRMSLCuL
where I
L(RMS)
=
is the RMS inductor current that
can be calculated as follows:
I
L(RMS)
= I
OUT(max)
1 +
1 ( IPP
3 I
) 2
OUT(max)
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
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Page 8
Output Capacitor Selection
APPLICATIONS INFORMATION
The required ESR (Equivalent Series Resis­tance) and capacitance drive the selection of the type and quantity of the output capacitors. The ESR must be small enough that both the resis­tive voltage deviation due to a step change in the load current and the output ripple voltage do not exceed the tolerance limits expected on the output voltage. During an output load transient, the output capacitor must supply all the addi­tional current demanded by the load until the SP7652 adjusts the inductor current to the new value.
In order to maintain V
the capacitance must
OUT,
be large enough so that the output voltage is held up while the inductor current ramps up or down to the value corresponding to the new load current. Additionally, the ESR in the output capacitor causes a step in the output voltage equal to the current. Because of the fast transient response and inherent 100% and 0% duty cycle capability provided by the SP7652 when ex­posed to output load transient, the output ca­pacitor is typically chosen for ESR, not for capacitance value.
The output capacitor’s ESR, combined with the inductor ripple current, is typically the main contributor to output voltage ripple. The maxi­mum allowable ESR required to maintain a specified output voltage ripple can be calculated by:
R
V
ESR
I
PK-PK
OUT
where: V
= Peak to Peak Output Voltage Ripple
OUT
I
= Peak to Peak Inductor Ripple Current
PK-PK
The total output ripple is a combination of the ESR and the output capacitance value and can be calculated as follows:
FS = Switching Frequency D = Duty Cycle
= Output Capacitance Value
C
OUT
Input Capacitor Selection
The input capacitor should be selected for ripple current rating, capacitance and voltage rating. The input capacitor must meet the ripple current requirement imposed by the switching current. In continuous conduction mode, the source cur­rent of the high-side MOSFET is approximately a square wave of duty cycle V
OUT/VIN
. Most of this current is supplied by the input bypass capacitors. The RMS value of input capacitor current is determined at the maximum output current and under the assumption that the peak
to peak inductor ripple current is low, it is given by:
I
CIN(rms)
= I
OUT(max)
D(1 - D)
The worse case occurs when the duty cycle D is 50% and gives an RMS current value equal to I
/2.
OUT
Select input capacitors with adequate ripple current rating to ensure reliable operation.
The power dissipated in the input capacitor is:
2
RIP =
)( CINESRrmsCINCIN
)(
This can become a significant part of power losses in a converter and hurt the overall energy transfer efficiency. The input voltage ripple primarily depends on the input capacitor ESR and capacitance. Ignoring the inductor ripple current, the input voltage ripple can be deter­mined by:
V
OUT
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
IPP (1 – D)
=
(
C
OUTFS
2
)
+ (IPPR
ESR
2
)
8
Page 9
APPLICATIONS INFORMATION
RIV
+=
)((m ax)
CINESRoutIN
)(
The capacitor type suitable for the output capac­itors can also be used for the input capacitors.
However, exercise extra caution when tantalum capacitors are used. Tantalum capacitors are known
OUTINOUTMAXOUT
2
VCF
ININS
transient response, but often jeopardizes the system stability. Cross over frequency should be higher than the ESR zero but less than 1/5 of the switching frequency. The ESR zero is con­tributed by the ESR associated with the output capacitors and can be determined by:
High cross over frequency is desirable for fast
)(
VVVI
for catastrophic failure when exposed to surge current, and input capacitors are prone to such surge current when power supplies are connected “live” to low impedance power sources.
Loop Compensation Design
The open loop gain of the whole system can be divided into the gain of the error amplifier,
ƒ
=
Z(ESR)
2π C
The next step is to calculate the complex conju­gate poles contributed by the LC output filter,
1
OUT RESR
PWM modulator, buck converter output stage, and feedback resistor divider. In order to cross over at the selected frequency FCO, the gain of the error amplifier has to compensate for the
ƒ
P(LC)
=
2π L C
1
OUT
attenuation caused by the rest of the loop at this frequency.
The goal of loop compensation is to manipulate loop frequency response such that its gain crossesover 0db at a slope of -20db/dec. The first step of compensation design is to pick the loop cross over frequency.
Type III Voltage Loop
Compensation
G
(s) Gain Block
AMP
+
V
REF
(Volts)
_
Notes: R
Condition: Cz2 >> Cp1 & R1 >> Rz3 Output Load Resistance >> R
SP7652 Voltage Mode Control Loop with Loop Dynamic
Definitions:
R
= Output Capacitor Equivalent Series Resistance
ESR
R
= Output Inductor DC Resistance
DC
R
RAMP_PP
= SP7652 internal RAMP Amplitude Peak to Peak Voltage
Conditions:
C
2 >> Cp1 and R1 >> RZ 3
Z
Output Load Resistance >> R
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
(SRz2Cz2+1)(SR1Cz3+1) (SR
SR1Cz2(SRz3Cz3+1)(SRz2Cp1+1)
= Output Capacitor Equivalent Series Resistance.
ESR
R
= Output Inductor DC Resistance.
DC
= SP6132 Internal RAMP Amplitude Peak to Peak Voltage.
V
RAMP_PP
& R
ESR
DC
V
FBK
(Volts)
and R
ESR
DC
When the output capacitors are of a Ceramic Type, the SP7652 Evaluation Board requires a Type III compensation circuit to give a phase boost of 180° in order to counteract the effects of an under damped resonance of the output filter at the double pole frequency.
PWM Stage
Gain
G
PWM
Block
V
IN
V
RAMP_PP
Voltage Feedback
G
Gain Block
FBK
R
2
or
(R
)
R
1
+
2
V
REF
V
OUT
[S^2LC
Output Stage G
ESRCOUT
+S(R
OUT
OUT
ESR+RDC
(s) Gain
Block
+ 1)
) C
+1]
OUT
V
OUT
(Volts)
9
Page 10
Gain
(dB)
20 Log (RZ2/R1)
Condition: C22 >> CP1, R1 >> RZ3
1/6.28 (R1) (CZ3)
1/6.28(R22) (CZ2)
1/6.28 (R1) (CZ2)
1/6.28 (RZ2) (CP1)
APPLICATIONS INFORMATION
Error Amplifier Gain Bandwidth Product
Frequency
(Hz)
1/6.28 (RZ3) (CZ3)
Bode Plot of Type III Error Amplifier Compensation.
V
RZ3
OUT
CZ3
R1
68.1k, 1%
R
SET
Type III Error Amplifier Compensation Circuit
R
SET
=54.48/ (V
OUT
-0.8)
(k)
5
VFB
-
+
+
-
CZ2
0.8V
CP1
RZ2
6
COMP
CF1
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
10
Page 11
TYPICAL PERFORMANCE CHARACTERISTICS
SP7652 Effi. vs Iout Plots @
96.0
Vin=8V, 12V, 15V, and Vout=5.0V
94.0
92.0
90.0
88.0
86.0
Efficiency (%)
84.0
82.0
80.0
Vin=12V Vin=8V
Vin=15V
123456
Load Current (A)
SP7652 Effi. vs Iout Plots @
93.5
Vin=5V, and Vout=3.3V
93.0
92.5
92.0
91.5
Efficiency (%)
91.0
90.5
90.0 123456
Load Current (A)
SP7652 Vout vs Iout Plots @
4.96
Vin=8V, 12V, and 15V
4.955
4.95
4.945
Output Voltage (V)
4.94
Vin=12V
Vin=8V
Vin=15V
0123456
Load Current (A)
SP7652 Vout vs Iout Plots @
3.31
Vin=5V, and Vout=3.3V
3.305
3.3
3.295
3.29
Output Voltage (V)
3.285
3.28 0 12345 6
Load Current (A)
SP7652 Effi. vs Iout Plots @ Vin=3.3V, and Vout=0.8V
80.0
79.0
78.0
77.0
76.0
75.0
74.0
73.0
Efficiency (%)
72.0
71.0
70.0
123456
Load Current (A)
SP7652 Vout vs Iout Plots @ Vin=3.3V, and Vout=0.8V
0.794
0.792
0.79
0.788
Output Voltage (V)
0.786
0 123456
Load Current (A)
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
11
Page 12
TYPICAL PERFORMANCE CHARACTERISTICS
100
90
80
70
Efficiency (%)
60
50
40
0123456
100
90
80
70
60
Efficiency (%)
50
40
Efficiency vs Output Load at 12Vin
Vout = 5.0V Vout = 3.3V Vout = 2.5V Vout = 1.8V Vout = 1.5V Vout = 1.0V
Load Current (A)
Efficiency vs Output Load at 3.3Vin
Vout = 2.5V
Vout = 1.8V
Vout = 1.5V
Vout = 1.0V
01234 56
Load Current (A)
100
90
80
70
Efficiency (%)
60
50
40
0123456
Efficiency vs Output Load at 5Vin
Vout = 3.3V Vout = 2.5V Vout = 1.8V Vout = 1.5V Vout = 1.0V
Load Current (A)
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
12
Page 13
PACKAGE: 26 PIN DFN
D
E
(7 x 4 mm)
Top View
A
A3
A1
L
J
Side View
e
K
b
E2
D2
SYMBOL
26 Pin DFN
MIN NOM MAX
D2
D3
Bottom View
A 0.800 0.850 0.900 A1 0.000 - 0.050 A3 0.178 0.203 0.228
b 0.170 0.220 0.270
D 6.950 7.000 7.050
D2 2.000 2.050 2.100 D3 1.780 1.830 1.880
e
0.500 BSC
E 3.950 4.000 4.050 E2 2.730 2.780 2.830
K 0.340 0.390 0.440
J 0.200 0.250 0.300
L 0.350 0.400 0.450
Note: Dimensions in (mm)
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
13
Page 14
ORDERING INFORMATION
Part Number Temperature Package
SP7652ER/TR ......................................... -40°C to +85°C ................................. 26 Pin 7 X 4 DFN
SP7652ER-L/TR .....................................-40°C to +85°C ............. (Lead Free) 26 Pin 7 X 4 DFN
/TR = Tape and Reel
Pack quantity is 3000 DFN.
CLICK HERE TO ORDER SAMPLES
Corporation
ANALOG EXCELLENCE
Sipex Corporation Headquarters and
Sales Office
233 South Hillview Drive Milpitas, CA 95035 TEL: (408) 934-7500 FAX: (408) 935-7600
Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others.
Date: 2/18/05 SP7652 Wide Input Voltage Range 6A, 600kHz, Buck Regulator © Copyright 2005 Sipex Corporation
14
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